Overall Objective: The basic objective is to determine how a mature ovarian follicle, which is destined to rupture, responds to a preovulatory surge of luteinizing hormone. Emphasis is on the chemical and cytochemical changes which occur within the follicle as it approaches ovulation. Current Goals: 1) Continue to study the properties of ovarian collagenolytic enzymes in Graafian follicles by utilization of reconstituted collagen gels and C14-glycine as the substrates for enzyme activity. 2) Complete the examination of the cytological distribution of acid phosphatase in ovulatory follicles. 3) Complete our current evaluation of the surface adhesions which hold the granulosa cells together in the mature ovarian follicle. 4) Complete an evaluation of changes in ovarian ascorbic acid in follicular tissue during ovulation.